针对一个吸气式高超声速飞行器模型,研究了其鲁棒变增益控制问题。为处理对建模误差的鲁棒性问题,将标准的线性变参数(Linear Parameter-Varying)控制算法扩展到对参数和动态不确定性具有结构摄动的鲁棒性框架内。基于对建模不确定性的积分二次型约束(Integral Quadratic Constraint)刻画,以定标的线性矩阵不等式(Linear Matrix Inequality)形式给出了其鲁棒控制算法。考虑到描述飞行器动态数值非线性模型的复杂性,建立了其解析形式的曲线拟合模型。基于此解析模型,推导了LPV模型用于控制设计和开环分析。设计了以动压和马赫数为增益变量的飞行控制系统。控制器设计将LPV控制器和变增益比例积分补偿器组合成内外环结构,实现了姿态稳定性和精确的轨迹跟踪性能。非线性仿真结果证实了算法和应用的有效性。
This paper addressed issues related to robust gain-scheduling control for a model of an air-breathing hypersonic vehicle. For dealing with the robustness problem with respect to modeling error,the standard control problem for linear parameter-varying (LPV) systems is extended to robustness framework with structural perturbation of parametric and dynamic uncertainties. Based on the characterization of modeling uncertainties via integral quadratic constraints (IQC),a robust control algorithm is presented in terms of scaled linear matrix inequalities (LMI). Because of the complexity of the numerical nonlinear model of the vehicle dynamics,a curve-fitted model in closed form is created. Based on the analytical model,a LPV model is derived for control design and open-loop analysis. A flight control system that takes dynamic pressure and Mach number as gain variables is designed. The controller design combines a robust LPV controller with a gain-scheduled proportional-integral compensator to constitute an inner/outer loop structure,thus achieving attitude stability and accurate trajectory tracking performance. Nonlinear simulation results are presented to demonstrate effectiveness of the algorithm and its application.